Incisal guide



June 2, 1925.

J. A. LENTZ INCISAL GUIDE Filed May 28, 1923 1119011101! J va/ 62155- A9) Patented June 2 1925.

. UNITED STATES.

' JOHN L mum, on .rnomux, amzoim.

worsen some.

Application filed May as,

To all z't mafi concern:

Be it known t at I, JOHN A. Lmrrz, a

citizen of the United States, and a resident of Phoenix, county of Maricopa, State of Arizona, have invented a new and useful Incisal Guide, of which the following is a ill specification.

The present invention relates to improvements inlncisal guides used in connection with dentalarticulators. A particular type of articulator is described in my copending application for an adjustable plane articul-ator, Serial No. 642,052 and the incisal .gnide sought to be protected by this application was primarilydesigned to be used in connection with the said articulator although not confined to the same exclusively. lVhile referring generally to the.said application it might be well to. set forth a few general principles necessary to explain the operation of the incisalguide forming the subject matter of the present application.

Dental articulators are used in arranging and articulating artificial teeth and their object is to provide means for disposing the upper jaw or maxillae and lower jaw or mandible in such a manner that they may be moved relative to one, another in a manner resembling natural movements of the mouth for which the teeth are intended. Commonly we are used to considering the maxillae in the human head stationary and the mandible movable relative to the maxillae. In an articulator however, it is more convenient to dis-' pose the mandible stationary and to move the maxillae about the mandible in order to bring about the movements desired.

The principal movements to be considered are the opening and closing of the mouth,

'the right and left lateral movements.

the protrusive or incisal movement, during which the mandible is pushed forward i lllld e opening and closing movement is carried out on a horizontal axis while the right and left lateral movements are made on substantially vertical axes. The principal difliculty in locating these horizontal and vertical axes r sults from the fact that neither the horizontal axis nor the vertical axes coinicide with any clearly defined structural lines in the human head. The horizontal axis is or dinarily assumed to lie in the nei hborhood of wthe condyles while the vertica axes are normall'y'di'sposed on either side of the center line'of the head substantially two inches away fromthe same, the right lateral moveleft lateral axis.

1928. Serial No. 642,053.

ment of the mandible being carried out on the right lateral axis while the left lateral movements of the mandible are made on the Neither are these lateral axes strictly perpendicular but normally converge upwardly to some slight extent.

We shall assume that the mandible is stationarily supported and that the maxillae is movable on the mandible and is supported in a frame which latter is secured at its rear end in such a manner as to allow the maxillae to move over the mandible in the same manner as the lower jaw moves relative to the upper jaw in the human head and that the frame extends forwardly of the upper jaw and is provided at its front end with a vertical pin adapted to ride on the incisal guide to be described hereinafter.

The preferred form of my incisal guide is shown in. the accompanying drawing in which Figure 1 represents a top .plan view of the same; Figure 2 a side elevation, Figure 3 a front elevation,-Figure 4 a vertical section along line H of Figure 1 and Figure' 5 a transverse section along line 5-5 of Figure 1. While I have shown only the preferred form of the invention it should be understood that various changes or modifications may be made within the scope of the claims heretov attached without departing from the spirit of the invention. I

My incisal guide is supported on a base plate (1) provided with two slots (2) adapted to recelve the screws (3) for securing the base plate to its support. A second plate (4:) is fixed to the base plate and provided with abutments (6) adapted to receive by means of a tongue and groove arrangement (7) the member ('8) which latter is allowed by the peripheral form of the engaging faces of the abutments to revolve about its pivot (9) and which may be set in any desired position by means of the set screws (11). From the member (8 rise in spaced frame and finally that it may be swung on a horizontal axis which latter also occupies a central position and therefore intersects the vertical axis referred to.

. The frameitself is of rectangular, almost square form and consists merely of two lateral strips of metal (19) and two transverse strl s (21) joined at the corners. The studs (14) previously referred to penetrate the walls of the side members 0f the frame centrally. Two other studs (22) are centrally supported in the transverse frame members (21) at the same elevation as the studs (14) and form ivots for end members (23) and (24) 'rism from two incisal blades (26) and (27 ese blades are two sections of a single plane dimensioned to fit in the frame and are adapted to be swung on saidpivots (22) into any desired angular relation relative to one another as shown in dotted lines in Figure 3. They may be set in any position by means of the milled nuts (28) 1 engaging bolts (29) passing through raised portions (31) of the front longitudinally the sectors normally, espeend members (24) and through curved slots (32) in the enlarged front member (21) ofthe main frame. I I

On the incisal blades is supported with freedom of sliding longitudinal motion a second frame (33) recessed to form a pcripheral abutment (34) and-cut l0ngitudi nally with its end members (36) and (37) pivoted on the longitudinal studs (22) previously mentioned so that the two sections of the sliding frame automalticallyfollow the motion of the incisal blades (26? and (27) about the studs (22). Lateral y the sections of the sliding rame (33) are slidably secured in lateral ,walls (38) rising from the incisal blades 26) and (27) by means of the dove tail arrangement shown at (39) in Figure 5.

The peripheral abutment (34) of the sliding frame (33) serves as a guide for two sectors (41) and (42), the arced outer faces of which slidably engage the abutment by means of the dove tail arrangement shown in section at (43) in Figure 5. The rear faces (44) of these sectors serve as lateral guide members. for a ball (46) disposed at the bottom end of the rod (47) ad ustably supported in the upper frame (48) of the articulator holding the model of the upper jaw. The construction of this upper frame is not shown in the drawing and my copending application previously mentioned is referred to in this connection. The rod may be straight or may be formed with a crank (51) in itscentral portion. The latter is introduced for the purpose of allow-" ing the central portion to bemoved sideways in case it obstructs the view. To

nuopao raising or lowering the same, its reduced upper end (50) is rotatably supported in the sleeve (55) and held against endwise motion by the nut (55) threadedly engaging its top end. The sleeve (55) itself threadedly en ages the upper frame member (48), as s own at (49) so that it, and the rod with it, may be vertically adjusted by rotating the sleeve by means of a wrench engaging the angular head (51') of the same. The guide faces (44) of the sectors (41) and" (42) are curved vertically to fit on the ball (46). They are also curved very slightly, preferably on a 5" radius, horitontally, the length of the radius corresponding approximately to the normal distance between the rod (47) and the vertical axes on which the lateral movements of the upper mandible are to be executed.

The two sectors (41) and (42) may be independently secured against sliding mo tion relative to the abutment by means of set screws (52) extending over the edge of the abutment and adapted to be screwed into tight engagement with the same.

When the'sliding frame (33) is moved cially when the set screws are tightened, move with the frame without changing their angular relation relative to one another. If

slots (58) in said members (56) and adapted to hold the latter against longitudinal motion. In this manner the sectors (41) and (42) may be moved longitudinally with the sliding frame (33) if the set screws (57) are loosened and the set screws (52) are tightened without changing their angular relation or they may be held against longitudinal motion by tightening the set screws (57) and loosening the set screws (52) in which latter case,v the studs 53) travel in lateral direction in the forks (54) and cause the angular relation of the guide faces (44) to be changed. 1

Sliding longitudinal motion is imparted to the sliding frame (33) in the following manner. The front end members (36) of the sliding frame which it will be remembered are pivoted on the stud (22) are held on the same against longitudinal motion by two collars (61) while the front end members (24) of the incisal blades (26) and (27) are slidably pivoted on the same stud.

-The stud (22) extends through a threaded sleeve (62) sliding motion will be imparted to the sliding frame (33) whereby the same may be moved substantially from the position shown in full lines in Figure 1 to that shown in dotted lines.

g It should be noted that during the progress ofthis longitudinal motion if the set screws (57) are tightened the sectors (41) and (42) rotate about the pivots (53) so as to assume the dotted line position shown in Figure 1 in which-the guide faces (44) are shownin alinement while the pivots (53) have traveled inwardly within the forks (54) and have reached an innermost osition also shown in dotted lines. It 'wil be understood that if during the travel of the sliding frame (33) from the full line position to the dotted line position the set screws (52) had been tightened and the set screws (57) had been loosened the sectors would have traveled along with the frame (33) without chang-.

ing their angular relation.

The studs (14) on which the main frame is pivoted have also indicating rods :13 (64; pivotally secured thereon which latter' vice having been so placed before mounting the models; that is to say the ball is disposed in'the vertex of the angle formed by the two guiding faces (44). This position may be considered the central position of the incisal'guide from which all the adjustments are made;

Next a protrusive bite is taken. In taking a protrus ve or incisive bite the lower jaw moves" straight or obliquely forward and downward relative to the upper jaw or con sidering the lower jaw stationary it might be said that the upper jaw moves straight or obliquely backward and upwardly relative to the lower jaw which motion would of course be followed by the ball (46). lVhen the protrusive bite is used and the upper jaw adjusted to thesame the ball will therefore bein a position rearwardly of its origi nal position and somewhat higher. Tocause the trough between the incisal blades, which during this motion may have lost the contact with the ball, to again touch the same the whole frame (13) is tilted on the studs (14) that is on a horizontal axis and if necessary on the/stud (9) on a vertical axis'until a contact is obtained on both sides of the trough in which position the frame (13) is are adapted to/be swung from an inactive secured by means of the nuts (16) and (11).

horizontal position into an active vertical position and are adapted to be held'in any desired position by means of a set screw (66) passing through a curvedslot (67) in a projection (68) of the adjoining frame member (19) and threadedly engaging the indicating rod. Rods of this character are preferably provided on either side for purposes set forth hereinafter. In,this connection it may be stated that the lower portion of rod (47) holding the ball (46) is per fectly cylindrical in form and that the width of the indicating rods (64) corresponds to the width of the rod (47 so that the three rods may be brought into exact alinement. V

The operation of the device is as follows:

, The general principle is to determine the normal closing position of the mouth in which position the models are mounted the rod (47 carrying the ball (46) will occupy a central'position relative to the whole de- First a central wax bite- In thisposition the incisal blades (26) and (27) will remain in contact/with the ball during any incisive motion of the upper jaw relative to the lower jaw and thus form a guide for such motion after the bite has been removed.

To adjust the sectors (41) and (42) and the guide faces (44) to the lateral movements of the jaws of the patient a right lateral bite is taken, that is a bite in which the lower jaw is in an extreme right position relative to the upper jaw or consider ing the lower jaw stationary in which the upper jaw is in extreme left position relative to the lower jaw. When this bite is introduced the ball will probably be found in a position considerably to the left of the longitudinal central line and somewhat protrusive you higher, than in its original position since most. lateral motions include forward motions and out of contact with the blade. The left -incisal blade (27) (looking at it from the place where.the mandibles would be, that is from the top of the sheet) is now turned on the longitudinal center llne until it again touches the ball and held by set screws (28) and at the same time the sector (42) is pushed into a position where its guiding face (44) makes contact with the ball in which position itis secured by tightening the set screw (52).' The same operation is performed relative to'the right-hand side of the incisal guide'which com letes the adjusting of the device; The bal may now be madeto ride over the incisal blades guide faces (44) and any motion that may durin are left. tightened and the screws (57) loosbe made will cause this portion of the upper jaw, that is the incisal point to move exactly in accordance with the movements of a similar point in the upper jaw of the patient relative to the mandible. Arbitrary changes according to aesthetic requirements or for other reasons can be made if desired.

If it is desired to execute a longitudinal movement in graduated stages it is accom plished by the operation of the adjustment screw (63) which causes the sliding frame (33) to move forward or backward: If this movement the set screws (52) ened the angular relation of the two guide faces (44) will not be affected. If it is desired, however, to execute a protrusive movement and to carry with it a lateral movement with the gradual approach of the guide faces (44) to a straight line the set screws (57 are tightened and the set screws (52) are losened. Under these conditions a sliding forward movement, of the sliding frame (33) will cause the sectors (41) and (42) to revolve on the studs (53) and to be moved into the position indicated in dotted lines in Figure 1.

here no other means are provided in the articulator for rotation around lateral axes, or rotation pointsin the horizontal plane, the guide face (44) of the respective sector (41) or (42) (disregarding, of course, any slight aberration due to minute discrepancies between the arc of face (44) and the true are of rotation) in combination with a maxillary pin, preferably in the median line (located rearward to correspond to the rearward location of the respective lateral rotation points around which the movement is to be made) and a mandibular slot or path for such pin (or the true path of any other" maxillary or mandibular point in the hori-' zontal plane) will give rotation around the true lateral rotation point in the horizontal plane. Special reference is made for a, further explanation of this feature to my copending application previously referred to. Where the articulator provides for rotation. around lateral axes or rotation points independent of the incisal guide but does not provide definite paths for intermediate movements the lateral paths of the incisal guide are useful in providing such definite movements.

Where it is desired to raise or lower the bite and the articulator is otherwise adapted to compensate for the changed relation the indicator rods (64) which normally are folded. away parallel with the frame (13) v are swung upwardly into alinement with the lower part. of the rod (47). The latter is then raised or lowered b means of the threaded engagement at 49) to-open or close the bite-whereupon the-frame (13) is moved forward or backward and tilted on its horizontal axis until it once more occupies a central position under the ball with the rod (47) alined-with the two indicator rods (64) whereby the original relations are reproduced. The indicator rods (64) may associated therewith for setting either section at a desired angle;

2. An incisal guide for an element of the character described, comprising a plane pivotally supported on a transverse horizontal axis, means for setting the plane in any desired position, said plane being longitudinally divided and hinged and having means associated therewith for setting either section at a desired angle and lateral guide members slidable on the two sections having means connected therewith for revolving the same about an imaginary center point.

3. An incisal guide for an element of the character described, comprising a plane pivotally supported on a transverse horizontal axis, means for setting the Plane in any desired position, said plane being longitudinally divided and hinged and having means associated therewith for setting either section at a desired angle and lateral guide members slidable on the two sections, having means connected therewith for moving the same longitudinally over the sections of the plane.

4. An incisal guide for an element of the character described, comprising a plane piv-,

otally supported on a transverse horizontal axis, means for setting the plane inany desired position, said plane being longitudinally divided and hinged and having means associated therewith for setting either section at a desired angle and lateral guide members slidable on the two sections, having coacting means connected therewith for revolving the same about an imaginary cen-. ter point whereby their angular relation is changed and for moving them longitudinally over the planes without changing their angular relation.

5. An incisal guide for an element terminatin in a ball of the character described comprising a plane pivotally supported on a transverse horizontal axisintersecting the vertical axis of the ball with freedom of rotary motion about the latter axis and adjusting means associated with either motion for holding the plane in a desired position.

1 ill) 6. An incisal guide for an element termia plane pivotally supported on a transverse horizontal axls intersecting the vertical axis of the ball, said plane being longitudinally divided and hinged on an axis passing through the center of the ball.

7. An incisal guide for an element tenninating in a ball at its lower end comprising a plane pivotally supported on a transverse horizontal axis intersecting the vertical axis of the ball, said plane being longitudinally divided and hinged on an axis passing through the center of the ball, with lateral guide members slidable on the two sections having means connected therewith for relgolfing the same about the center of the al l i 8. An incisal guide for an element terminating in a ball at its lower end comprising a plane pivotally supported on a transverse horizontal axis intersecting the vertical axis of the ball, said plane being longitudinally divided and a. hinged on an axis passing through the center of the ball, with lateral guide members slidable on the two sections having means connected therewith for moving the same longitudinally (aver the said sections.

9. An incisal guide for an element terminating in a ball at its lower end compris ing a plane pivotally supported on a transverse horizontal axis intersecting the vertical axis of the ball, said plane being longitudinally divided and hinged on an axis passing through the center 'of the ball, with lateral guide members slidable on the two plane sections having coacting means connected therewith for revolving the same her and about the center of the ball whereby their angular relation is changed and for moving them longitudinally over the planes without changing their an ular relation.-

10. In an incisal guide or an element of the character described a plane disposed so as to allow the element to ride on the same and lateral guide "members for the element havin means associated therewith for changing their angular relation comprising a sector connected with each guide mempleripherally disposed abutments en.- gaging t e circumferential faces of the sectors for defining their. path of travel.

11.. In an incisal guide for an element of the character described a plane disposed so as to allow the element to ride on the same and lateral guide members for the element having means associated therewith for changing their angular relation comprising a sector connected with each guide member, peripherally disposed abutments slidably engaging the circumferential faces of the sectors and means for moving the abutments longitudinally over the plane while holding one point of each sector against longitudinal motion,

12. In an incisal uide for an element of the character descrified, a plane disposed so as to allow the element to ride on the same and lateral guide members for the element having means associated therewith for changing their angular relation comprising a sector connected with each guide member, peripherally disposed 'abutments slidably engaging the circumferential faces of the sectors, means for moving the abutments longitudinally over the plane and means for holding one point of each sector against longitudinal motion comprising fixed members slotted transversely and a pin rising from each sector engaging said slotted member.-

13. In an incisal guide for an element of changing their angular relation comprising a sector connecte with each guide member, peripherally disposed abutments slidably engaging the circumferential faces of the sectors, means for moving the abutments longitudinally over the plane and means for holding one point of each sector against longitudinal motion comprising fixed members slotted transversely and a pin rising from each sector engaging said slotted mem'-' ber, sa-id fixed members having means associated therewith for making the same slidable and allowin the sectors to move longitudinallywith t e abutments without changing their angular relation.

JOHN A. LENTZ. 

